From DE 925 203 A a ball bearing cage of the construction noted above is known. The two cage halves are here riveted in the area of connecting sections or connected to each other by a special connecting structure formed by the cage halves.
From DE 39 39 438 A1 a ball bearing cage for a grooved ball bearing is likewise known that is assembled from two ring elements. The ring elements are shaped so that the ball guide pockets formed therein have a non-round contour in a top view of a ball guide pocket.
Finally, from DE 36 40 633 A1 another ball bearing cage assembled from two ring elements for a grooved ball bearing is known in which the contact plane between the two ring elements is offset in the axial direction relative to a ball center plane defined by the ball pocket centers.
Sheet metal cages with inner, spherically concave pockets (ball-shaped pockets) are used to a great extent in grooved ball bearings. The cage is here typically made from two ring-shaped cage halves that are assembled in the axial direction and can be connected to each other in different ways (e.g., riveted cages, tabbed cages, and welded cages). The balls are here guided into the functional position (installed in the bearing) by the cage in the ball-shaped pockets. Here, care must be taken that the cage remains guided by a roller body, i.e., the cage does not contact the bearing rings. The roller body guide or the radial play is defined by the ring domed geometry of each ball guide pocket. The design/definition of the unsupported ball span is typically tailored to the ideal geometry. The radial clearance is here defined by the diameter of the cage pocket at the cage outer edges.
Sheet metal cages of this construction are produced by punching (cutting). Thus, all of the punching surfaces on one side have a punch entry and on the other side a punch outlet/punching burr. In order to not disrupt the movement of the ball (noise, friction), the punching direction is normally selected so that the punch entry is on the inside of the ball pocket. Because the sheet metal is also thicker with increasing ball diameter, the dimension of the punch entry also increases. Consequently, the unsupported ball span is large and the cage can run, under some circumstances, on the bearing ring.